질문하다([jil-mun-ha-da/ask]) means to ask a question. In polite speech, say 질문해요([jil-mun-hae-yo]).
질문했어요([jil-mun-hae-sseo-yo/asked]) is the polite past form. Example: 선생님께 질문했어요 (I asked the teacher).
질문해야 해요([jil-mun-hae-ya hae-yo/have to ask]) means you must ask. Example: 지금 질문해야 해요 (I have to ask now).
질문하다([jil-mun-ha-da/ask]) means "to ask". It is used when you say a question to get information.
1. Daily: “숙제를 질문해요 (suk-je-reul jil-mun-hae-yo)”
2. Past: 질문했어요([jil-mun-hae-sseo-yo/asked]) asked.
3. Duty: 질문해야 해요([jil-mun-hae-ya hae-yo/have to ask]) have to ask.
4. Warning: 질문하지 마세요([jil-mun-ha-ji ma-se-yo/don't ask]) don't ask.
A: What do you ask?
B: 숙제를 질문해요. B: suk-je-reul jil-mun-hae-yo.B: I ask about the homework.
A: 왜 질문해요? A: wae jil-mun-hae-yo?A: Why do you ask?
B: 몰라서 질문해요. B: mol-la-seo jil-mun-hae-yo.B: I ask because I don't know. - 질문하다([jil-mun-ha-da/ask])
A: Did you ask yesterday?
B: 네, 질문했어요. B: ne, jil-mun-hae-sseo-yo.B: Yes, I asked.
A: 뭘 질문했어요? A: mwol jil-mun-hae-sseo-yo?A: What did you ask?
B: 숙제를 질문했어요. B: suk-je-reul jil-mun-hae-sseo-yo.B: I asked about the homework. - 질문했어요([jil-mun-hae-sseo-yo/asked])
A: When do you have to ask?
B: 지금 질문해야 해요. B: ji-geum jil-mun-hae-ya hae-yo.B: I have to ask now.
A: 뭘 질문해야 해요? A: mwol jil-mun-hae-ya hae-yo?A: What do you have to ask?
B: 방법을 질문해야 해요. B: bang-beo-beul jil-mun-hae-ya hae-yo.B: I have to ask about the method. - 질문해야 해요([jil-mun-hae-ya hae-yo/have to ask])
• 질문하다([jil-mun-ha-da/ask]) ask
- 질문했어요([jil-mun-hae-sseo-yo/asked]) asked
- 질문하고 싶어요([jil-mun-ha-go si-peo-yo/want to ask]) want to ask
- 질문해야 해요([jil-mun-hae-ya hae-yo/have to ask]) have to ask
- 질문하지 마세요([jil-mun-ha-ji ma-se-yo/don't ask]) don't ask